Tailoring antihypertensive treatment for special populations

AIH-APRIL 1999-VOL. 12, NO. 4, PART 2

SPECIAL SYMPOSIA

Wednesday, May 19, Astor Ballroom, 10:00 AM to 12:30 PM Tailoring Antihypertensive Treatment for Special Populations

Wednesday, May 19, Astor Ballroom, 10:00 AM to 12:30 PM Tailoring Antihypertensive Treatment for Special Populations

H y p e r t e n s i o n and Atrial F i b r i l l a t i o n James A. Reiffel, M. D. Columbia University, New York, N.Y.

HYPERTENSION, CONGESTIVE HEART FAILURE AND CORONARY ARTERY DISEASE Franz H. Messerli, MD, Ochsner Medical Institutions, New Orleans, Louisiana Arterial hypertension is a powerful independent risk factor for congestive heart failure (CHF), coronary artery disease (CAD) and other cardiovascular morbidity and mortality. Data from the Framingham cohort document that over 80% of the patients with CHF have a history of essential hypertension. The sustained increase in arterial pressure in patients with essential hypertension leads initially to concentric and subsequently to eccentric left ventricular hypertrophy to compensate for the increased hemodynamie burden. Finally, when the ventricle is no longer able to compensate for the everincreasing afterload, a decrease in ejection fraction ensues, which clinically manifests itself in CHF. The relationship between CAD and essential hypertension is even more complex. Hypertension by itself is a well-known risk factor for CAD and seems to directly promote atherogenesis. However, sustained arterial hypertension also gives rise to left ventricular hypertrophy which, by itself, increases the risk for myocardial iscbemia because it unfavorably affects the oxygen supply/demand equilibrium of the myocardium. In hypertensive patients with concomitant CHF or CAD, the selection of first line antihypertensive therapy should be modified according to the underlying pathogenesis of the concomitant cardiovascular condition. An ACE inhibitor or an angiotensin receptor inhibitor is the drug of choice in the patient with CHF, possibly in combination with a diuretic. In contrast, in patients with CAD, either a beta-blocker or a calcium antagonist should be considered. However, although this "two-for-one" concept is attractive, it never has been proven to be true and therefore will have to be substantiated by morbidity and mortality studies. Key Words: Hypertension, congestive heart failure, coronary artery disease, ACE inhibitor, calcium antagonist

Hypertension (HTN) reduces LV compliance, increases L A p r e s s u r e and stretch, and alters atrial electrophysiology. These effects increase atrial fibrillation (AT). HTN reduces AF tolerance: reduced LV filling, LA emptying, and higher p u l m o n a r y v a s c u l a r p r e s s u r e s occur with A F in a less compliant LV and increase congestive symptoms and/or reduce cardiac output. HTN increases the complications of AF: HTN is one of the markers of high embolic risk in AF. Importantly, HTN also alters therapeutic choices in AF. Calcium channel blockers become first line choices for rate control (and LVH resolution and HTN control) with beta blockers as alternatives. W a r f a r i n becomes the indicated anticoagulant. When sinus rhythm is required, antiarrhythmic selection begins with a class IC agent, such as p r o p a f e n o n e or flecainide. These are both non organ toxic and have the lowest p r o a r r h y t h m i c incidence in the normal ventricle and in the ventricle with only mild or moderate LVH, as in most hypertensives. LVH decreases outward K ÷ currents, increases action potential duration, and thus increases the potential for torsade de pointes. (The risk of K ~ channel blocking antiarrhythmicsl, m a k i n g class IA and III agents somewhat riskier. D i u r e t i c s may also increase torsade incidence due to r e d u c e d K + and Mg ~. Ischemia/strain or fibrosis/wide QRS would, however, increase class IC p r o a r r h y t h m i c risk and shift the first line choice to sotalol. Finally, HTN is a risk factor for coronary a r t e r y disease which further alters AG tolerance and therapy selection.

Wednesday, May 19, Astor Ballroom, 10:00 AM to 12:30 PM Tailoring Antihypertensive Treatment for Special Populations HYPERTENSION AND DIABETES George L. Bakris, Rush Presbyterian-St Luke's Medical Center, Chicago, IL A number of studies including the recent United Kingdom Prospective Diabetes Study (UKPDS), indicate that the presence of hypertension ha a person with Type 2 diabetes is the most powerful comorbid condition that predicts development of a cardiovascular event. Numerous other studies indicate that lowering blood pressure also slows renal disease progression. A review of recent studies indicate that blood pressure must be lowered to levels of < 130/85 m m H g in order to maximally slow renal disease progression and reduce cardiovascular events (Bakris GL Diabetes Rev & Clin. Res.;1998;37). This is further exemplified by both the Hypertension Optimal Treatment Trial (HOT} as well as the SYST-EUR trial. A recent analysis of all clinical trials in persons with diabetic nephropathy, demonstrates that blood pressure reduction to levels of < 130/85 rnmHg maximally slows declines in renal function. Furthermore, these analyses demonstrate that an average of 3.8 different antihypertensive medications must be given to achieve these lower levels of blood pressure. Thus, fix-dose combination anlLlaypertensive medications have a clear role in trealSng such patients since they w o u l d improve compliance, achieve blood pressure control and reduce morbidity as well as minimizing sideeffect profiles. These formulations n o w allow physicians to use two different combinations to treat difficult patients with hypertension, thus combining four medications into two pills. Key Words:

Diabetes, Proteinuria, Nephropathy, Hypertension

Wednesday, May 19, Broadway Ballroom South, 4:00 PM to 6:30 PM Unmet Needs in the Treatment of Hypertension Hypertension (HTN) and Unmet Needs, a Global Perspective Edward J. Roccella, Ph.D., M.P.H. National Heart, Lung and Blood Institute, Bethesda, MD. A literature review was conducted to determine the HTN prevalence, awarenesS, treatment, and control rate throughout the world. Virtually all nations define HTN as 140/90 mm Hg., though treatment may begin at 160/95 mm Hg. HTN prevalence ranges between 15 and 35 percent of populations. The differences may be due to measurement techniques, the mean age of the population, and demographic factors. Men have higher prevalence rates than women. Awareness rates for HTN vary by nation with the highest rates found in United States (70%). Worldwide, women are more likely to be aware of their HTN than men. The best HTN control rates have yet to achieve 30 percent. It is concluded that about one-fifth of the world's population has elevated blood pressure. HTN awareness rates range from 15 to 35%. Treatment for HTN ranges between 10 and 55% of the HTN population. Because uncontrolled HTN causes strokes, heart attack and kidney disease, HTN remains a very important global public health problem. As public health measures continue to reduce acute infectious diseases and the world's population ages, chronic disease, especially those exacerbated by uncontrolled HTN. if left unabated will become an even larger global public health problem. Key Words: Hypertensi°n Awareness, Treatment and Control

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